Armed members of the Central African Republic's former rebel coalition looted and burned down about 100 houses last week, African military officials said Monday, the latest unrest to hit the chronically unstable country.

"The village of Vacap and parts of the village of Yongoro went up in flames," an officer of the African-led stabilization force MISCA told Agence France Presse on condition of anonymity. "Villagers' property was destroyed by fire. They all fled to the scrubland."

A top U.N. official warned Friday that anarchy in Central African Republic risks becoming "genocide" as armed Christian and Muslim groups battle each other.

The giant but impoverished nation has slid into lawlessness since rebels overthrew President Francois Bozize in March. France has called for a U.N. peacekeeping force to be deployed and is increasing its own military presence there.

The U.N. Security Council on Tuesday approved sending a special 250-strong military force to protect U.N. workers in increasingly chaotic Central African Republic, diplomats said.

U.N. leader Ban Ki-moon asked for the special force last week because of the anarchic conditions in the impoverished nation where rebels seized power in March.

Almost 40 people were killed in weekend fighting between armed vigilantes and former rebels near Bouar in western Central African Republic, the army said Tuesday, issuing a new toll.

"The fighting last Saturday between self-defense militias and ex-rebels killed almost 40 people, including at least 35 in the ranks of the militias, with several wounded," a source close to the general staff said.

Twelve people were killed in fierce clashes over the weekend between vigilante groups and former rebels in the western Central African town of Bouar, according to a military source Sunday.

The updated death toll came after militias armed with machetes encircled Bouar, a town some 400 kilometers (250 miles) northwest of the capital Bangui on Saturday morning, the same source said on condition of anonymity.

Hundreds of vigilantes armed with machetes and firearms attacked the town of Bouar in western Central African Republic on Saturday, forcing civilians to flee the area, a military source and residents said.

Self-defense groups called "Anti-balakas, equipped with weapons of war and machetes surrounded the town early this morning and shots from light and heavy firearms could be heard in several areas of Bouar," the military source said.

Strife-torn Central African Republic is on the brink of a far deeper crisis, a senior U.N. aid official warned Friday, as the country's new rulers defended their human rights record.

"The situation is critical and requires our urgent attention. We have been very heavily focused on Syria, and the Sahel, which is of course understandable, but this is a place which requires our full support," said Ted Chaiban, emergencies director at the world body's children's agency UNICEF.

African leaders meeting in Chad agreed Monday to boost the powers of a peacekeeping force in the strife-torn Central African Republic, saying the troops must "immediately disarm and drive out" foreign armed groups.

"Heads of state and government demand that the MISCA force deploy throughout the Central African Republic, disarm and drive out all foreign armed elements without delay," the leaders of the 10-nation ECCAS regional grouping said in a statement.

European Union ministers on Monday urged an international force slowly deploying to the strife-torn Central African Republic to mobilize, declaring the deteriorating security situation there "alarming".

EU ministers gathered at talks in Luxembourg said in a statement that the U.N.-ordered, African-led stabilization force requires more teeth on the ground and needs "urgent operational implementation".

Doctors Without Borders (MSF) on Wednesday denounced the "unprecedented" violence in the Central African Republic, urging all sides to respect civilian safety and calling for urgent international aid.

"Tens of thousands of villagers have fled a fresh wave of attacks summary executions, perpetrated both by armed groups and government forces in the northwest of the country," the NGO said.